During industrial fabrication of products made from plural components, components made from different and/or identical materials have to be bonded together by material engagement. For example, the joining technique is used in the motor vehicle industry when mounting front windows and rear windows etc. of vehicles. Herein, high quality glue joints between glass and metal have to be fabricated which comply with pertinent safety requests and/or warranty requirements of manufacturers for such joints.
It is known in the art that, initially, the components have to be cleaned from adhering contamination or protective oil films when producing a glue joint with two components. It is furthermore known to treat a surface of a component with a primer, which is a surface adhesion enhancement agent, in order to improve or enable the adhesion of components.
U.S. Pat. No. 7,467,452 B2 discloses a method for applying flowable materials, in particular glue, on components of products to be produced where the surface of the components before applying the flowable materials is cleaned, for example, through plasma or a flashlight. Herein, the flashlight can also be used for heating the surface of the component. Furthermore, also applying a primer after cleaning the surface and before applying flowable materials is known in the art.
The publication “Development of an adhesive-primer for polypropylene composites” by David-Trudel-Boucher, Tan Minh Ton-That and Johanne Denault, Industrial Materials Institute, National Research Council of Canada describes an adhesion capable primer or adhesion enhancement agent which enables or improves gluing polymers and in particular polypropylenes together.
In glue joints of components, however, in many cases only portions of the surfaces of the components have to be connected. This is the case in particular for glass windows of vehicles where only a narrow outer edge of the glass window is glued together with the body of the vehicle.
Furthermore, ever faster manufacturing processes demand shorter cycle times for producing safe glue joints. The critical time in these processes is the drying time or also airing time of the primer. The airing time is the time required by the primer to prepare the surface for gluing and to completely evaporate or ventilate air from the surface after being applied to the surface. Gluing can only be performed after completely airing the primer from the surface.
At present, solvent primers are being used in joining surface treatment devices and joining surface treatment methods for glass windows of vehicles like, for example, black primer which is a primer with soot particles mixed therein. A black primer of this type at an ambient temperature of approximately 20° C. has an airing time of approximately 30 seconds. In view of the required acceleration of production processes, however, this airing time is not short enough. Furthermore, it is also disadvantageous that when mixing the soot particles into the primer typically the soot particles are also distributed in the surrounding area. Subsequently, the soot particles included in the black primer are distributed into the surrounding area while airing the primer. Furthermore, it is detrimental for the environment that the black primer includes solvents which are released into the environment while airing the black primer. All these effects are undesirable. The requirements for cleaning the surface treatment device and/or the superordinated equipment as well as the components and also the effort for maintaining the required quality standards for the vehicle are increased.